1. Field of the Invention
The present invention relates to an air conditioning system for a vehicle, and in particular to an air conditioning system mountable in the rear of a vehicle.
2. Description of the Related Art
Typically, a vehicle air conditioning system is mounted within the front of a vehicle, more particularly, within an instrumental panel thereof.
Recently, an air conditioning system has been developed which comprise an integral unit including an evaporator and a heater core. The evaporator is a heat exchanger providing a cooling capability and the heater core is a heat exchanger providing a heating capability. Thereby, the system provides an improved space availability in the lower area of a passenger compartment and also a reduction of the manufacturing cost.
Examples of the vehicle air conditioning system of the type having the integrated evaporator and heater core unit are disclosed in Japanese Patent Unexamined Publication Nos. 10-250344 and 10-250345. In the vehicle air conditioning system of these publications, the heater core is disposed behind the evaporator, and each of the heater core and the evaporator is in an upright position.
On the other hand, the conventional front-mounted air conditioning system of the above-mentioned type is not fully satisfactory in a so-called minivan having a larger compartment space due to a shortage of air conditioning capability thereof. To overcome this problem, an additional rear-mounted air conditioning system can be often installed in a space defined between a wheel housing for a rear wheel and a D-pillar (the most-rearward pillar-post of the vehicle).
However, such a space between the wheel housing for the rear wheel and the D-pillar is small and specifically the space is limited in a vehicle front-to-back direction. Further, the minivan-type vehicles may utilize sliding doors useful in providing a large opening through which passengers get on or off in order to give an easy access to the second and/or third rear seats for any passengers or occupants. Due to this, the rear wheel wells are displaced backward to some extent, which in turn may tend to further limit the space between the wheel housing and the D-pillar.
As a result, the rear-mounted air conditioning system must be installed in the limited space between the wheel housing and the D-pillar.
However, the conventional air conditioning systems as disclosed in the publications are relatively long in the vehicle front-to-back or longitudinal direction and therefore are difficult to conveniently install in the rear of the vehicle due to the space requirements.
It is therefore an object of the present invention to provide to provide an air conditioning system for vehicle having a reduced longitudinal dimension suitable for mounting in the rear of the vehicle.
The above object is achieved according to the first aspect of the present invention by providing an air conditioning system mountable in the rear of a vehicle having a vent mode and a foot mode, the air conditioning system comprising a casing, an evaporator mounted at an upper front portion within the casing, a heater core mounted below the evaporator such that the evaporator and the heater core are not superposed when seen in a vehicle front-to-back direction, a temperature controlling damper for controlling a rate of air which is directed toward the heater core so to attain a selected final temperature of the air which is discharged into a passenger compartment of the vehicle, a vent outlet provided at an upper rear portion of the casing for allowing the air having the selected temperature to be discharged into the passenger compartment in the vent mode, and a foot outlet provided at the front portion of the casing for allowing the air having the elected temperature to be discharged into the passenger compartment in the foot mode.
According to the first aspect of the present invention, since the evaporator and the heater core are not superposed when seen in a vehicle front-to-back direction, such arrangement provides a reduced longitudinal dimension of the air conditioning system, so that it can be conveniently located in a limited space between a wheel housing for a rear wheel and a D-pillar.
In the preferred embodiment of the present invention, the temperature controlling damper controls the rate of the air which is directed toward the heater core after flowing through the evaporator.
In the still preferred embodiment of the present invention, the temperature controlling damper controls the rate of the air which is directed toward the heater core before flowing through the evaporator.
The present invention also provides, in a second aspect, an air conditioning system mountable in the rear of a vehicle having a vent mode and a foot mode, the air conditioning system comprising a casing, an evaporator mounted at an upper front portion within the casing, a heater core mounted below the evaporator such that the evaporator and the heater core are not superposed when seen in a vehicle front-to-back direction, a vent outlet provided at the upper rear portion of the casing for allowing the air having a first selected final temperature to be discharged into the passenger compartment in the vent mode, a foot outlet provided at the front portion of the casing for allowing the air having a second selected final temperature to be discharged into the passenger compartment in the foot mode, a first bypass passage extending between the downstream side of the evaporator and the vent outlet, a second bypass passage extending between the downstream side of the evaporator and the foot outlet, a first heater core passage providing a fluid communication between the rear side of the heater core and the first bypass passage, a second heater core passage providing a fluid communication between the front side of the heater core and the second bypass passage, and a temperature controlling damper for controlling rate of air which is directed toward the heater core so as to attain the first or second selected temperature of the air which is discharged into a passenger compartment of the vehicle.
In a preferred embodiment of the present invention, the temperature controlling damper controls a proportion in which the rate of the air is divided into the first bypass passage and the second bypass passage.
The present invention provides, in a third aspect, an air conditioning system mountable in the rear of a vehicle having a vent mode and a foot mode, the air conditioning system comprising a casing, an evaporator mounted at the upper front portion within the casing, a heater core mounted below the evaporator such that the evaporator and the heater core are not superposed when seen in a vehicle front-to-back direction, a vent outlet provided at an upper rear portion of the casing for allowing the air having a first selected final temperature to be discharged into the passenger compartment in the vent mode, a foot outlet provided at the front portion of the casing for allowing the air having a second selected final temperature to be discharged into the passenger compartment in the foot mode, a first passage extending between the downstream side of the evaporator and the vent outlet, a first heater core passage providing a fluid communication between the rear side of the heater core and the first passage, a second heater core passage providing a fluid communication between the front side of the heater core and the upstream side of the evaporator, and a temperature controlling damper for controlling rate of air which is directed toward the heater core so as to attain the first or second selected temperature of the air which is discharged into a passenger compartment of the vehicle.
In a preferred embodiment of the present invention, the temperature controlling damper controls the rate of a portion of the air to flow through the evaporator and the rate of the remaining air to bypass the evaporator and flow through heater core in a controlled proportion.
In a still preferred embodiment of the present invention, the air conditioning system further comprises a drain passage disposed below the evaporator for draining a condensate from the evaporator, the drain passage having a generally funnel-like configuration.
In a further still preferred embodiment of the present invention, the temperature controlling damper has a projecting member integrally formed with the face of the damper facing the second heater core passage.
The above and other objects and features of the present invention will be apparent from the following description made with reference to the accompany drawings showing preferred embodiments of the present invention.